“When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That’s relativity.”

That was Albert Einstein’s way of trying to explain his theory of relativity, a theory which also explains gravity. But as good scientists know, any theory should be tested repeatedly.

That’s just what scientists at the Max Planck Institute for Radioastronomy in Germany did in a recent study where they examined two stars orbiting each other 7,000 light years away, according to The Wall Street Journal[1]. One is a white dwarf while the other is a pulsar, which spins 25 times every second.

Einstein’s theory says objects with mass curve space-time, an effect perceived as gravity. But his theory about gravity does not explain many phenomena in nature and is at odds with quantum theory, which examines objects at the atomic and subatomic level.

Scientists seek to test Einstein’s theory in hopes of understanding how it fits with other theories. That’s where the German study comes in.

The gravity on the pulsar’s surface is 300 billion times more than Earth’s, closer to that of a black hole, which even light cannot escape.

The two stars orbiting each other, losing energy over time, moving closer together spinning around each other faster than before.

Following Einstein’s theory, the time it takes for the stars to orbit each other should shrink by about eight-millionths of a second per year.

The German scientists used telescopes to measure the two stars, finding the results matched Einstein’s theory exactly.

The first time Einstein’s theory was confirmed came during a solar eclipse four years after his theory was published. It made him a celebrity overnight.

He was asked how he would have felt if he hadn’t been proven right.

“I would have felt sorry for the Lord,” Einstein said. “The theory is correct.”